GEN-ERIC News

“The man who says he is willing to meet you halfway is usually a poor judge of distance.”

MIT researchers have created a new structured gel that can rapidly change color in response to a variety of stimuli, including temperature, pressure, salt concentration and humidity. Among other applications, the structured gel could be used as a fast and inexpensive chemical sensor, said Edwin Thomas, MIT’s Morris Cohen Professor of Materials Science and Engineering. One place where such an environmental sensor could be useful is a food processing plant, where the sensor could indicate whether food that must remain dry has been overly exposed to humidity. Thomas is senior author of a paper on the work to be published in the Oct. 21 online edition of Nature Materials. Structured gels are those that feature an internal pattern such as layers. A critical component of the structured gel developed at MIT is a material that expands or contracts when exposed to certain stimuli. Those changes in the thickness of the gel cause it to change color, through the entire range of the visible spectrum of light. Objects that reflect different colors depending on which way you look at them already exist, but once those objects are manufactured, their properties can’t change. The MIT team set out to create a material that would change color in response to external stimuli.

Genuine mood lighting just took a step closer. A shape-shifting lampshade can monitor brightness and movement in a room and then gently adjust the amount and quality of light it emits. Brainchild of London-based designer Assa Ashuach, the AI Light consists of a light bulb surrounded by a flexible nylon “skeleton” that forms two lobes. Thin rods running through the centre of each lobe are controlled by built-in motors. They can rotate and bend to shape the skeleton in different ways. More light shines through areas where the skeleton is spread out, while squashed regions emit less. So different combinations of rod position create a range of light quality.

Microscopic particles can be steered through the tiny channels of a microfluidic chip using light, US researchers have shown. They modified standard piece of lab equipment to direct particle traffic using light, and say the trick could prove vital for rapid chemical and biological analysis with handheld devices. Microfluidic chips contain microscopic tubes that can be used to ferry cells and particles around for chemical or biological experimentation. Controlling fluids and particles at small scales is difficult, however. The US team, led by David Erickson and Michal Lipson at Cornell University, Ithaca, US used light to control these unruly particles. They constructed a microfluidic chip with “waveguides” built into the walls of each fluid channel. The waveguides were designed to act like leaky pipes: as laser light passes through, it does not bounce perfectly off the inside walls, and a weak electromagnetic field – called the evanescent field – leaks out. Mystery ‘cushion’Particles that flow across a waveguide’s path are captured by its electromagnetic field and pulled along in the same direction as the light inside the waveguide. The approach can even steer particles around a bend.

Researchers at The University of Manchester have developed high-tech battery-powered textile yarns that can be used to make clothing glow in the dark. Current high visibility products – such as those used by emergency services, cyclists and highway maintenance workers – depend on external light sources to make them visible. They can be ineffective in low light situations and require a light source from something like vehicle headlights to make them visible. The latest development, made from electroluminescent (EL) yarns, allows the wearer to be permanently visible and therefore improves personal safety. EL yarn is a novel technology, which emits light when powered by a battery. Its development has been based on thin film electroluminescent technology. The yarn consists of an inner conductive core yarn, coated with electroluminescent ink – which means it emits light when an electric current is passed through it – and a protective transparent encapsulation, with an outer conductive yarn wrapped around it. When the EL yarn is powered with an inverter the resultant electrical field between the inner and outer conductor causes the electroluminescent coating to emit light. The emission of light occurs between the contact points between the outer yarn and the inner yarn.

A university professor of physics has made a radio out of a single carbon nanotube that’s about 10,000 times thinner than a human hair. It runs on batteries and you need headphones to use it, but it tunes in stations on the FM dial. Radio has gone nano. Electrical engineers at the University of California, Irvine, have built a radio receiver that uses a carbon nanotube as a key component. Peter J. Burke and Chris Rutherglen employed the nanotube as a demodulator—a device that translates radio waves into sound. The UC Irvine team grew nanotubes on high-resistivity silicon and then grafted palladium electrodes onto the wafer using optical lithography. For the demodulator, the researchers selected devices in which a lone nanotube bridges the gap between electrodes. They then incorporated the nanotube demodulator into an AM radio receiver. Using an iPod and an AM signal generator as their broadcasting system, Burke and Rutherglen showed they could wirelessly transmit music to the nanotube receiver system while maintaining high audio quality.

Syrdec, a Princeton, N.J.-based company is working on a material that, when combined with another substance, will generate electricity with ambient room heat, Andrew Surany, the company’s president, told CNET News.com this week. Conceivably, one could take that material and fashion it into a passive fuel cell that can create power by just sitting in an ordinary room heated to about 72 degrees Fahrenheit, leading to self-charging electronic devices. “It derives heat from the environment” and converts it to electricity, Surany said. “I’m talking about embedding cells into doors or the panels on a car. In a laptop, I am talking about embedding cells into the case.”

Two regions of the brain linked to optimism have been discovered by researchers. The identification of the sites that signal positive thinking could shed light on the causes of depression, they say. The US team says that the act of imagining a positive future event – such as winning an award or receiving a large sum of cash – activates two brain areas known as the amygdala and the rostral anterior cingulated cortex (rACC). The finding lends weight to earlier studies that suggested these brain regions malfunction in depression and hint at new ways of diagnosing the disorder.

Feeling like playing hooky, but nervous about getting caught? The Excused Absence Network has your back. For about $25, students and employees can buy excuse notes that appear to come from doctors or hospitals. Other options include a fake jury summons or an authentic-looking funeral service program complete with comforting poems and a list of pallbearers. Some question whether the products are legal or ethical - or even work - but the company’s owners say they’re just helping people do something they would have done anyway. “Millions of Americans work dead-end jobs, and sometimes they just need a day off,” said John Liddell, co-founder of the Internet-based company Vision Matters, which sells the notes as part of its Excused Absence Network.